Between putting in long hours at work and catching up with friends, it can be hard to find solid quality time with your guy.

But keep this in mind next time you're tempted to do a double-date to squeeze in everyone at once instead of going solo with your man: New research has found that couples who spend a good chunk time alone together once a week are three times more likely to say that they're "very happy" in their relationship.

For their study, researchers from the University of Virginia's National Marriage Project surveyed 1,600 couples and asked them about everything from relationship satisfaction to sex.

They discovered that couples who spend at least one night a week alone together say they're more committed to their relationship than those who don't hang out together as much. Oh, and couples who do those date nights are more than three times more likely to say that they're "highly satisfied" with their sex lives.

Of course, recent research found that spending time with other couples is good for your relationship too, but be sure to spend enough solo time with your guy as well.

Bottom line: Whether you stay in and catch up on re-runs of 30 Rock or go out to a nice dinner, quality time with your man will keep both of you happy…and keep the sex amazing.